Homer rents the family the movie Paint Your Wagon. He and Bart expect to see a violent Western starring Lee Marvin, Clint Eastwood and someone who appears to be Lee van Cleef. However, the movie turns out to be a musical. This causes Homer to dispose of the tape and condemn singing, but Marge says that Homer often sings. To prove her point, she tells of past occasions of Homer and other Springfieldians breaking into song.

Ultimately, this allows clips of the following songs from these episodes to be shown:

The family's singing motivates Snake Jailbird to come in; he is bothered by the Simpsons' singing and constantly tries to kill them, ironically doing his own singing. At first, when he wanted to kill them, he didn't have a gun, so he left to get one. Later, he came back with a gun and pointed it at the Simpsons but had no bullets so he left again to get ammo. Near the end, he was finally going to kill them, but the singing ended and he had no reason to kill them, so he left again. But when Marge was pulling down the banner, she was humming the main theme, so Snake fired a bullet, breaking the glass. Marge then quickly said that she was done singing (or humming). During the closing credits, Snake can be heard trying to prevent the theme music from playing in the background, having grown annoyed with music over the course of the episode.